Pituitary Stalk Interruption Syndrome

Abstract

Pituitary Stalk Interruption Syndrome (PSIS) is a rare anatomical defect resulting from impaired hypothalamic-pituitary communication due to the absence, thinning, or disruption of the pituitary stalk. The precise pathogenesis remains unclear. It is hypothesized that damage to the normally developed pituitary stalk may result from birth trauma, asphyxia, or organogenesis defects during embryogenesis. This damage may be related to genetic and environmental factors. Genetic studies have focused on the signaling pathways implicated in pituitary development, including Wnt, Notch and Shh, as well as other growth factors. Despite the identification of 224 different genetic mutations associated with the disease, the genotype-phenotype relationship has not been clearly elucidated. The clinical manifestations of the disease are highly variable. Neonates frequently present with panhypopituitarism clinically. The most common symptoms observed in neonates are hypoglycemia, prolonged or cholestatic jaundice, hypotonia, cryptorchidism, and micropenis. Another common finding is the occurrence of seizures associated with hypoglycemia or electrolyte imbalance and central hypothyroidism. Extrapituitary malformations are present in approximately half of the patients diagnosed during the neonatal period. Magnetic resonance imaging (MRI) represents the gold standard for diagnosis. The treatment plan is based on the replacement of the deficient hormone. The early recognition of the symptoms of this rare syndrome in the neonatal period, together with pituitary imaging in the potential patient population, is made possible by the knowledge of the extra-pituitary malformations that may be associated with this disorder. Early diagnosis and the initiation of effective treatment can prevent disease-related mortality and morbidity. It is essential that long-term, multidisciplinary, and family- integrated follow-up and treatment plans are implemented in order to improve survival rates and quality of life.